In recent years, an exponential growth of communication systems especially wireless communication systems has been observed. At first, the great success of wireless communication systems is essentially explained by the mobility they enable. Mobility is, by nature, coupled with uncertainty. However, uncertainty is often not desired in applications like industrial manufacturing, network organization, and many other applications. Local positioning or locationing is the only means to efficiently overcome this uncertainty. Security and integrity also benefit strongly from locationing. Hence, there is a well-established demand for the ability to track the location of various objects and/or persons within a wireless communication system or network.
Locating a device in a wireless communication network may be accomplished by measuring the differences in arrival times of radio frequency (RF) packets at three or more spatially separated receivers or locationing receivers (LRs), even without the knowledge of the time of transmit. The most difficult task to accomplish in this scheme, is the synchronization of time-stamping clocks among all the LRs. Traditionally, this is achieved by a variety of hardware methods such as distributing a highly stable clock via coax, or, over the air via RF broadcast. However, this involves a lot of cost.
Accordingly, there is a need for a method and apparatus for locationing an object in a communication network
Skilled artisans will appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help to improve understanding of embodiments of the present invention.
The apparatus and method components have been represented where appropriate by conventional symbols in the drawings, showing only those specific details that are pertinent to understanding the embodiments of the present invention so as not to obscure the disclosure with details that will be readily apparent to those of ordinary skill in the art having the benefit of the description herein.